Variable drain flow restrictor

ABSTRACT

A proportioning valve for a reverse osmosis system that controls the production of product water by the differential pressure across the purification membrane. By sensing increasing tank pressure to actuate the proportioning valve, the flow of waste water is restricted. Placement of seals within the cavity of the valve, as well as placement of waste water inlet and outlet ports, protects tension components that provide reverse tank pressure from waste water exposure. A needle valve assembly responsive to an actuating assembly that senses tank pressure removes the need for an inlet tank water port while restricting water flow.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The invention relates to reverse osmosis (RO) residential/commercialdrinking water systems, and more specifically to an apparatus and methodfor reducing the generation of waste water outlet in an RO system.

2. Description of Related Art

Osmosis is a naturally occurring phenomenon and one of the mostimportant processes in nature. It is a process where a weaker salinesolution will tend to migrate to a strong saline solution; that is, asolution that is less concentrated will have a natural tendency tomigrate to a solution with a higher concentration. Reverse osmosisoccurs when the solution is moved across a membrane against theconcentration gradient, from lower concentration to higherconcentration. For example, under normal osmosis, a semipermeablemembrane with fresh water on one side and a concentrated aqueoussolution on the other side would have the fresh water cross the membraneto dilute the concentrated solution. In reverse osmosis, pressure isexerted on the side with the concentrated solution to force the watermolecules across the membrane to the lower concentration side.

Reverse osmosis is utilized as a water purification technology employinga semipermeable membrane to remove larger particles from drinking water.A semipermeable membrane is a membrane that will allow some atoms ormolecules to pass but not others. Reverse osmosis can remove many typesof molecules and ions from solutions, including bacteria, and is used inboth industrial processes and the production of potable water. Thepredominant removal mechanism in membrane filtration is straining, orsize exclusion.

The desalinated water that is demineralized or deionized is typicallycalled permeate (or product) water. In a one stage RO system, the feedwater enters the RO system as one stream and exits the RO as concentrateand permeate water. The water stream that carries the concentratedcontaminants that did not pass through the RO membrane is called thewaste (reject or brine) stream.

Generally, in an RO system, water containing impurities enters thesystem where the impurities are stopped and rejected at the membranesurface. Water pressure then forces water molecules through themembrane. The purified water is then sent directly to the faucet.Impurities are then expelled from the system and sent to a drainunderneath the sink area.

As a consequence of an RO system, a portion of the water supply must beused to flush the contaminants to drain. Thus, there is a usage (waste)factor that can represent a significant portion of the total water use.

In U.S. Pat. No. 8,083,936 issued to Walker on Dec. 27, 2011 titled“REDUCING WASTE WATER IN REVERSE OSMOSIS RESIDENTIAL DRINKING WATERSYSTEMS,” an RO system is taught where the production of product wateris controlled by differential pressure across the purification membrane.As the tank pressure increases, the differential pressure decreases, anda reduced production of product water results. The increasing tankpressure is utilized as a force to actuate a valve that proportions thewaste water (a proportioning valve) generally in a relationship to theproduct water. In this manner, the ratio between the product water andthe waste water remains constant during the period that the purifiedwater is being delivered to the holding tank.

FIG. 1 depicts a proportioning valve of the prior art. In thistechnology, proportioning valve 10 is inserted within an RO system. Inthe RO system, as pressure is increased in the system's storage tank,pressure tank water enters inlet 12. A piston 14 in the proportioningvalve is forced through an O-ring 15 located within a piston housing 16,relocating the piston's position relative (and proportional to) achannel 18 in the piston, which is V-shaped, along and inside thesurface portion of the piston. This V-shaped channel 18 slowly decreasesin depth as it moves towards seal 13 on the piston. The channel beingwidest and deepest at the end proximate the ingress port 22. This allowsthe system to shut off when the tank pressure reaches approximatelytwo-thirds of the line pressure, designed because of diminishing returnsof product water in relation to waste water. A return spring 19 residesat the passage or channel end of the piston in a housing 20. Rejectwater enters the proportioning valve through ingress port 22 in pistonhousing 16. Reject water exits the proportioning valve through egressport 24 of housing 20 depending upon the positioning of piston 14. Wastewater passes through V-shaped channel 18 and the passage surrounded byO-ring 15, and is discharged through egress port 24.

One of the deficiencies with the prior art design is that water entersthe spring chamber where it can rust and degrade the life of the spring.Another deficiency is the inability to adjust the proportioning valve toaccommodate the particular RO system in which it operates. A thirddeficiency is the application of numerous mechanical components thattend to degrade and/or fail over time.

SUMMARY OF THE INVENTION

Bearing in mind the problems and deficiencies of the prior art, it istherefore an objective of the present invention to provide aproportioning valve for an RO system capable of protecting its internalworkings from contamination due to exposure to reject water.

It is another objective of the present invention to provide aproportioning valve for an RO system that can compensate for variationsin different RO systems, as well as the degradation of thereverse-pressure producing mechanism(s) within it.

The above and other objects, which will be apparent to those skilled inthe art, are achieved in the present invention which is directed to aproportioning valve for a reverse osmosis system comprising: acylindrical housing having an internal cavity with a product water inletproximate one end of the housing; a reject water inlet downstream of theproduct water inlet but not in fluid communication with the productwater inlet; a reject water outlet downstream of, and at times in fluidcommunication with, the reject water inlet; a slider within the housingresponsive on a first end to pressure provided by the product waterinlet and on a second end responsive to pressure provided by a reversepressure mechanism designed to partially counter the pressure providedby the product water, the slider having a channel exposed to the rejectwater inlet, the channel slidably exposed to the reject water outletwhen the slider moves and the channel is placed in fluid communicationwith the reject water outlet; and at least one seal to keep reject waterfrom entering a portion of the internal cavity that houses the reversepressure mechanism.

The channel is V-shaped, semi-circular, square, a flat incline, or othershape having varying width and/or depth and/or length extending axiallyalong a portion of the slider. The slider may accommodate a plurality ofchannels.

The reverse pressure mechanism may include a spring in mechanicalcommunication with the slider at one end, and located within theinternal cavity second portion.

The internal cavity second portion may include a tension adjustmentassembly to set tension of the spring. The tension adjustment assemblymay be in the form of an adjustable set screw in rotationalcommunication at one end with the spring, and having a knob foreffecting rotation at an opposite end.

The slider may also include a slider extension adjacent to or integralwith the slider, the slider extension in mechanical communication withthe reverse pressure mechanism.

In a second aspect, the present invention is directed to a proportioningvalve for regulating fluid flow in a system having set line fluidpressure, the valve comprising: a housing having an internal cavity, afirst fluid ingress port, a second fluid ingress port, and a fluidegress port, a first portion of the internal cavity adapted to house asliding mechanism, and a second portion of the internal cavity adaptedto house a reverse pressure mechanism; the first fluid ingress port influid communication with an external fluid reservoir having an inputfluid pressure; the sliding mechanism comprising: a slider or piston influid communication at an end face proximate and exposed to the firstfluid ingress port such that the slider is slidably responsive to theinput fluid pressure; a first seal located circumferentially about theslider prohibiting fluid flow from the first fluid ingress port past theseal towards the second portion of the housing, thereby maintaining theinput fluid pressure on the slider; a channel extending axially along aportion of the slider at an end of the slider proximate the secondportion of the internal cavity, the channel directing fluid from thesecond fluid ingress port into the internal cavity and towards thesecond fluid egress port; a slider extension in mechanical communicationwith, attached to, or integral with, the slider, located at the end ofthe slider proximate the second portion of the housing; a second seal inslidable communication with the slider extension, the second sealpositioned to ensure fluid from the first fluid ingress port to thefluid egress port does not enter the internal cavity second portion andexpose the reverse pressure mechanism to fluid; and an air vent locatedwithin the internal cavity second portion to release air pressure whenthe slide moves in a direction towards the internal cavity secondportion; wherein the proportioning valve stops fluid flow from the fluidegress port when the input fluid pressure reaches a predetermined limitof the set line fluid pressure.

In a third aspect, the present invention is directed to a proportioningvalve for a reverse osmosis system comprising: a housing having aninternal cavity with a reject water inlet proximate one end of thehousing; a reject water outlet downstream of the reject water inlet; aneedle valve assembly for restricting flow of water from the rejectwater inlet to the reject water outlet, the needle valve assemblyresponsive to a sensor.

The needle valve assembly may include a spindle having a shaped endportion at one end, the spindle in communication with an actuatingassembly, wherein the actuating assembly is responsive to the sensorsuch that movement of the actuating assembly causes axial or radialtranslation of the spindle and the shaped end portion of the spindle toform an orifice with a complementary shaped portion of the internalhousing or a complementary shaped component within the internal housingto restrict water flow when the spindle is axially or radiallytranslated, moving the spindle toward the complementary housing or theshaped component.

The spindle shaped end portion is preferably cone-shaped, and thecomplementary shaped portion of the internal housing is cone-shaped, orthe complementary shaped component is cone-shaped.

The needle valve assembly may include: a spindle having a shaped endportion at one end and a threaded portion at the opposite end, theshaped end portion of the spindle forming an orifice with acomplementary shaped portion of the internal housing or a complementaryshaped component within the internal housing; and a spindle drive inrotational communication with the spindle, the spindle being threadablyinserted within a complementary threaded cavity of the spindle drive,such that when the spindle drive is rotated, the threaded cavity of thespindle drive engages the threaded portion of the spindle, which drivesthe spindle either axially away from, or towards the complementaryhousing or the complementary shaped component, to restrict water flowwhen the spindle is moved toward the complementary housing or thecomplementary shaped component.

Additionally, a motorized assembly may be utilized in conjunction withthe proportioning valve, the motorized assembly being responsive to thesensor such that engagement of the motorized assembly with the spindledrive causes axial translation of the spindle such that the shaped endportion of the spindle forms an orifice with the complementary shapedportion of the internal housing or the complementary shaped componentwithin the internal housing.

The spindle may include a flange having at least one slot or groove, andthe housing internal cavity having at least one complementary axialprojection for receiving the at least one slot or groove to prohibit thespindle from rotating when the spindle is engaged by the actuatingassembly.

A seal may be situated proximate a junction of the spindle drive and thespindle, the seal assists in keeping reject water from entering thespindle drive side of the proportioning valve.

The proportioning valve may further include an end cap for securing thespindle drive within the housing, the end cap having an aperture forreceiving a shaped end protrusion of the spindle drive adjacent end, theprotrusion exiting the housing and the end cap, and slidably engagedwith a mechanized worm wheel, such that when the worm wheel is rotatedat a rotation that is responsive to a particular tank pressure, thespindle drive rotates and axially displaces the spindle.

Alternatively, the proportioning valve may include a needle valveassembly that comprises a spindle having a shaped end portion at one endand a threaded portion at the opposite end, the spindle in communicationwith an actuating assembly, wherein the actuating assembly includes anelectrical impulse driven motorized assembly or a non-electricaldrive-driven gear assembly, and is responsive to the sensor, the sensorsensing tank water pressure, water level in a pressurized orunpressurized storage tank, conductivity, or flow rate of the rejectwater, or any combination thereof, such that movement of the actuatingassembly causes axial or radial translation of the spindle which movesthe shaped end portion of the spindle towards a complementary shapedportion of the internal housing or a complementary shaped componentwithin the internal housing to form a restricting orifice that restrictswater flow.

The sensor senses tank water pressure, water level in a pressurized orunpressurized storage tank, conductivity, or flow rate of the rejectwater, or any combination thereof, in the reverse osmosis system.

The spindle may include a threaded portion opposite the shaped endportion, the threaded portion in rotational communication with anactuating assembly, wherein the actuating assembly is responsive to thesensor such that movement of the actuating assembly causes axial and/orradial translation of the spindle and the shaped end portion of thespindle to form an orifice with a complementary shaped portion of theinternal housing or a complementary shaped component within the internalhousing to restrict water flow when the spindle is axially and/orradially translated, moving the spindle toward the complementary housingor the shaped component.

In each embodiment, the proportioning valve is configured to be added toa residential reverse osmosis drinking water system that modulates thewaste water flow in proportion to the product water flow based on inputfrom the sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the invention believed to be novel and the elementscharacteristic of the invention are set forth with particularity in theappended claims. The figures are for illustration purposes only and arenot drawn to scale. The invention itself, however, both as toorganization and method of operation, may best be understood byreference to the detailed description which follows taken in conjunctionwith the accompanying drawings in which:

FIG. 1 depicts a proportioning valve of the prior art;

FIG. 2A depicts a first embodiment of a proportioning valve of thepresent invention having an air vent;

FIG. 2B depicts a proportioning valve of the present invention having atension adjustment assembly with an adjustable air vent capability;

FIG. 3 depicts an exploded view of the proportioning valve of FIG. 2;

FIG. 4 depicts a cross-sectional view of the end of the proportioningvalve of FIG. 2 showing a spring tension adjustment assembly of anadjusting screw located within a nut housing, and forming air ventsegments;

FIG. 5 depicts a slider having a plurality of channels on its outersurface for directing reject water flow;

FIG. 6 is an assembled, perspective view of the proportioning valve ofFIG. 2;

FIG. 7 depicts an exploded view of another embodiment of the presentinvention, where the spring tension mechanical components and the springhousing are removed and replaced by an alternate mechanism;

FIG. 8 depicts a cross-section of the housing of FIG. 7, depicting slotsin a spindle flange of a needle valve;

FIG. 9 is a perspective view of the proportioning valve incorporating aneedle valve (absent a spring tension mechanism), where the needle valveforms a narrowing annular ring with the cone-shaped internal wall of thehousing to restrict water flow during operation;

FIG. 10 is a partial schematic cross-sectional view of a variation onthe motorized proportioning valve of FIG. 7;

FIG. 11 depicts a side cross-section of the needle end portion of aneedle valve with the internal wall of the cone-shaped housing, and aforward cross-section depicting the annular egress port formed whenneedle end portion enters the cone-shaped internal wall;

FIG. 12A depicts a schematic cross-sectional view of a partialproportioning valve housing having an enhanced set screw configurationfor adjusting spring tension in the embodiments that employ a spring;and

FIG. 12B depicts a schematic isometric view of the spring stop of FIG.12A, showing an opening for receiving the driver key.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

In describing the preferred embodiment of the present invention,reference will be made herein to FIGS. 1-12 of the drawings in whichlike numerals refer to like features of the invention.

FIG. 2 depicts a first embodiment of a proportioning valve 100 of thepresent invention. In this embodiment, fluid, such as reject water in areverse osmosis system, is redirected away from the proportioning valveinternal mechanical components that establish the reverse pressure inthe valve to counter the incoming tank water pressure. That is, bydesign a portion of the proportioning reverse pressure mechanismcomponents remain dry and free from exposure to the reject water. Unlikethe prior art, the reject water egress port is not placed downstream ofthe internal mechanical components that establish the reverse pressurein the valve. Pressure tank water inlet 112 is located in a similarmanner as depicted in the prior art, shown here with an elbow fitting tothe receiving end of the cylindrical housing of proportional valve 100.Although an elbow fitting is depicted, other fittings are envisioned toprovide the necessary connection to the RO system.

A slider or piston 114 in proportioning valve 100 includes a slider seal113, preferably in the form of a wiper seal or other slidably sealingO-ring configuration, disposed on a first end proximate pressure tankwater inlet 112, which allows the ingress tank water to provide pressureto slider 114 while sealing the tank water from flowing over the slider,and simultaneously forcing the slider axially towards the center ofproportioning valve 100. Slider or piston 114 slides within acylindrical slider housing 116 against the bias of a reverse pressurecomponent (that is, a component that provides a pressure on the sliderin opposite direction to the pressure applied to the slider by the inputtank water, such as a spring or other tension forming component 119,which is located in housing. For exemplary purposes, the reversepressure mechanism shall be described as a spring 119 within a springhousing 120; however, other opposing pressure creating components may beemployed with minimal design alteration, while remaining consistent tothe teaching of the present invention.

The sliding is performed without the inlet tank water seeping past theslider to the spring housing. A reject water inlet 122 is positionedintermediate the ends of slider housing 116 such that channel 118, whichis axially located on the outer surface of slider 114, is in fluidcommunication with reject water inlet 122, and under certain pressureconditions, simultaneously in fluid communication with reject wateroutlet 124.

Channel 118 is preferably formed as a V-shaped channel extending about ⅓to about ⅔ of its length. The V-shaped channel 118 slowly decreases indepth as it moves on piston 114 towards seal 113. Channel 118 is widestand deepest at the end proximate seal 115, and may vary in length and/orwidth. The “V” of the channel may have an angle of approximately 90degrees for ease of manufacture; however, the shape of the channel isarbitrarily selected predicated upon the amount of reject waterpredetermined to traverse the channel and the amount of comparativetension between the bias spring and the reject water tank pressure.Other channel shapes may be implemented, and as noted below, more thanone channel may be incorporated on the piston surface.

In proportioning valve systems, as currently envisioned, the valve isdesigned to shut the system off when the tank pressure reachesapproximately two-thirds of the line pressure, although otherpredetermined limits are possible and adjustable by the length and depthof the channel(s) located on the piston, as well as by an adjustment ofreverse pressure exerted by the spring 119.

Reject water outlet 124 is positioned at the end of spring housing 120adjacent slider housing 116 and reject water inlet 122. Reject wateroutlet 124 is in fluid communication with reject water inlet 122 viachannel 118. When slider 114, forced by tank water pressure (andcorrespondingly biased by spring 119 in the opposing direction), ispositioned so that channel 118 directs fluid from reject water inlet 122to reject water outlet 124. Unlike the prior art, reject water outlet124 is not positioned to have reject water flow into the spring housingcavity where the spring resides.

An O-ring seal or wiper seal 115 is located at the end of slider 114 andpreferably does not extend beyond reject water outlet 124. An extensionpiece or cross slider 134 of slider 114 provides a necessary extensionof the slider's length to achieve axial displacement of channel 118without exposing the “dry side” of the proportioning valve to rejectwater. Cross slider 134 is designed to permit water to flow from channel118 to reject water outlet 124 while displacing spring 119. Cross sliderseal 117 is located at or near the end of cross slider 134 proximatespring 119 in order to form a water-tight seal during axial movement,and block any excess reject water from entering spring housing 120.

FIG. 3 depicts an exploded view of the proportioning valve of FIG. 2.Cross slider 134 is depicted having an X-shaped cross-section for themajority of its body length with predominantly a solid end abuttingspring 119 with cross slider seal 117. Cross slider seal 117 ispreferably a wiper seal, designed to form a water-tight seal with theinternal wall of spring housing 120. Each channel or groove 136 in crossslider 134 is designed to allow water to flow from channel 118 to rejectwater outlet 124. The grooves 136 formed within cross slider 134 make itpossible to receive water from multiple channels 118 in slider 114 anddirect this water to reject water outlet 124. Although an X-shapedcross-section is depicted for cross slider 134, other shapes that wouldallow water flow while providing structural support against the biasforce of spring 119 are not excluded and may be employed as a sliderextension. Having a plurality of grooves 136 in cross slider 134provides multiple avenues for water flow from channel 118 to rejectwater outlet 124, and reduces the weight of the slider extension, whilemaintaining structural integrity.

When piston 114 is acted upon by tank water pressure, cross slider 134slides along slider housing 116 and grooves 136 are exposed to theegress port of reject water outlet 124 enabling water to flow fromreject water inlet 122 to reject water outlet 124. Cross slider seal 117is located approximately at the junction of cross slider 134 and spring119, and may be attached to either cross slider 134 or at the end ofspring 119, or both.

In order to ensure that reject water does not flow into the springhousing 120 where spring 119 is located, cross slider seal 117 slidablyengages the inner cavity of spring housing 120 in a fluid-tight manner.The presence of cross slider seal 117 on the end of slider or piston 114or alternatively on the end of spring 119 ensures that water does notenter the spring chamber where spring 119 is located. Additionally, froma manufacturability stand-point, the introduction of wiper sealsaccommodates variation in the annular space of the slider housing andspring housing cavities, which may result from draft in molded plasticfabrication.

During operation of proportioning valve 100, under tank pressure thatexceeds the bias force of spring 119, reject water flows through channel118 into grooves 136 of cross slider 134. Grooves 136 are exposed to,and in fluid communication with, reject water outlet 124, which permitsreject water ingress to exit the proportioning valve via grooves 136 tothe reject water outlet 124.

An air vent 126 is introduced to allow the slider to move axially alongthe spring housing cavity without undue opposing air pressure that couldotherwise adversely affect the differential pressure necessary to reactproperly to the reject water flow. In one embodiment, the air vent maysimply be a hole located through spring housing 120. Since theintroduction of wiper seals removes the possibility of reject waterentering the spring housing 120, an air vent in the spring housing doesnot pose a leakage concern. Alternatively, the air vent may be formed incombination with a spring tension adjustable assembly explained herein.

An embodiment having a tension adjustment assembly with an adjustableair vent capability is depicted in FIG. 2B. In this embodiment, the airvent circumferentially surrounds an adjustable component 128, such asfor example a set screw, which upon rotation provides adjustment to thespring tension. This adjustment allows for the introduction of differenttypes of springs (different lengths, spring force, spring constants,etc.), which simplifies part selection during manufacture. Theadjustment also allows for predetermined or in-situ adjustment of thespring's bias force against different tank pressures. Adjustable setscrew 128 works in conjunction with a securing nut 129 having a centeraperture for receiving set screw 128. In this embodiment, the air vent126 is segmented by ribs 132 about the outer periphery of set screw 128.

FIG. 4 depicts a cross-sectional view of the end of proportioning valve100 showing the tension adjusting screw 128 located in nut 129, andforming air vent segments 126. The components forming the spring tensionadjustment assembly with air ventilation are preferably held in place bya fastener or retaining ring 130, such as a circlip, a C-clip, or snapring, which preferably is a semi-flexible metal ring with open endswhich can be snapped into place, situated in a machined groove to permitrotation but to prevent lateral (axial) movement.

Adjustable component 128, depicted here as a set screw having a turningknob with a threaded portion, maintains tension on spring 119 and allowsfor a tension adjustment after fabrication, which may be a factoryadjustment or a field adjustment. Adjustable component 128 also providesgreater flexibility in the spring selection since specific tension canbe adjusted, altered, and/or pre-set by knob 128. Adjustable component128 may also be a slidable resilient disc or other adjustable mechanismfor providing adjustable linear (axial) tension to spring 119.

In at least one embodiment, channel 118 in the piston is V-shaped,semi-circular, square, a flat incline, or other shape having varyingwidth and/or depth and/or length along and inside the surface portion ofthe slider. Also, unique to the seal placement of the present design, itis possible to include multiple channels 118 a-c on the slider asdepicted in FIG. 5. The channels may all be alike, or may have differentconfigurations that enable the overall release of reject water in apre-determined fashion having variation not otherwise capable of beingduplicated by a single channel.

FIG. 6 is an assembled, perspective view of the proportioning valve 100of FIG. 2. The proportioning valve is designed to shut off when the tankpressure reaches a predetermined value, such as a predeterminedpercentage of the line pressure. This eliminates the diminishing returnsof product water in relation to constant waste water flow. Theproportioning valve operation is governed by the input tank pressure,insomuch as the valve is designed to be responsive to varying tankpressure.

FIG. 7 depicts an exploded view of another embodiment of the presentinvention. In the first embodiment, a cross slider 134 having a crossslider seal 117 keeps reject water from entering the spring housingcavity, and redirect the reject water to the reject water egress port124 via a channel 118 in piston or slider 114. In this alternativeembodiment, the spring, spring housing, as well as the input tank waternecessary to create the pressure for moving the slider, are eliminated.

A needle valve assembly is introduced to regulate or restrict the flowof the reject water to drain, predicated on an adjustable actuatingassembly responsive to the tank water pressure. Preferably, theactuating assembly is responsive to tank water pressure via pressuresensor input, or to water pressure in a pressurized or unpressurizedstorage tank (for example, but not limited to, a countertopconfiguration), or to water weight in a pressurized or unpressurizedstorage tank, or to conductivity or flow rate of the reject water. Theadjustable assembly may be motorized, electrical impulse driven, or anon-electrical drive-driven gear assembly. Unlike the first embodimentor the prior art, a spindle drive 204 in mechanical, rotationalcommunication with a spindle 210 form the components that effectrestricted water flow. Spindle 210 includes a cone-shaped, needle endportion 212, which together with a complementary shape of theproportioning valve housing or a complementary shaped component placedwithin the housing, is utilized as part of the needle valve assemblythat serves to restrict flow based on its proximity to the complementaryhousing portion and the size of the orifice it creates.

This embodiment does not require a slidable piston, nor does it requirea formed channel within the outer surface of a slider or piston torestrict the water flow. In FIG. 7, proportioning valve 200 includes anadjustable component 202, such as a knob or worm wheel, which isresponsive to a rotary mechanism (not shown) to provide in-situadjustment to the (threaded) spindle drive 204, which in turn translatesthe rotational motion into axial movement of spindle 210 and needle endportion 212 against internal wall 214 of the proportioning valve housingthat is a complementary cone-shaped enclosure. Spindle 210 is threadablyinserted within a complementary threaded cavity of spindle drive 204,such that when spindle drive 204 is rotated, the threads on the spindledrive internal wall and the threads on the outer surface of spindle 210rotatably engage, which drives spindle 210 either axially away from, ortowards, internal wall 214 (depending upon the direction of rotation).Spindle 210 includes intermediate flange 217 that aids in centeringspindle 210 within housing 220. In at least one embodiment, intermediateflange 217 circumferentially surrounds spindle 210 in a radiallysegmented fashion, with each radial segment separated by a slot orgroove 225 that opens to the inner wall of housing 220. The inner wallof housing 220 includes linear, axial projections 227 that are slidablyengaged in slots 225 when spindle 210 axially translates about housing220. This configuration ensures that needle end portion 212 is centeredabout cone-shaped internal wall 214, and avoids rotation of spindle 210during axial translation. The slot/groove configuration of the spindleand internal wall housing may be replaced with anotherrotation-inhibiting mechanism, and the present invention is not limitedto any particular spindle rotation-inhibitor. FIG. 8 depicts across-section of housing 220 depicting projections 227 for slots 225 inspindle flange 217.

A seal 222 is situated at the junction of spindle drive 204 and spindle210 which assists in keeping reject water from entering the spindledrive side of proportioning valve 200. End cap 221 secures spindle drive204 within the proportioning valve housing 220, while providing anaperture 224 that allows a shaped end segment a square thread or knob205 for example at the end of spindle drive 204 to exit the housing andbe slidably engaged with mechanized worm wheel 202. In this manner, whenworm wheel 202 is rotated by a motorized mechanism having a rotationthat is responsive to a particular tank pressure, spindle drive 204rotates and axially displaces spindle 210 because spindle 210 cannotrotate due to the engagement of grooves or slots 225 on flange 217 withaxial projections 227 on the inner housing wall. The axial movement ofspindle 210 moves needle end portion 212 closer to, or further from, thecone-shaped internal wall 214, thus varying the size of the orificecreated by needle end portion 212 and internal wall 214 of theproportioning valve housing that is a complementary cone-shapedenclosure, thereby regulating reject water flow from reject water inlet216 to reject water outlet 218.

FIG. 9 is a perspective view of proportioning valve 200. Needle valve212 forms a narrowing annular ring with cone-shaped segment 214 torestrict flow during operation. Axial projections 227 are depicted onthe inner housing wall and align with grooves 225 on flange 217.

FIG. 10 is a partial schematic cross-sectional view of a variation onthe motorized proportioning valve of FIG. 7. In this embodiment, aworm-drive motor 302 actuates a worm-drive 304 within proportioningvalve housing 301. A spindle drive (not shown) and spindle 308(partially shown) would be similar to the design of FIG. 7, oralternatively, only an externally threaded spindle would be needed toengage and interact with the worm-drive motor threads 303. A sensor,such as a pressure transducer, senses the tank pressure status andactuates the worm-drive motor 302 to open or close the orifice of theneedle valve in a similar fashion as the embodiment depicted in FIG. 7.Alternatively, a paddle wheel could actuate and drive the gears. It mayalso be possible for the paddle wheel to monitor flow with properfeedback to a central processing unit.

FIG. 11 depicts a cross-section of the needle end portion 312 with theinternal wall 314 of the cone-shaped housing. An orifice or annularegress port 330 is formed when needle end portion 312 enters cone-shapedinternal wall 314, as shown in the expanded view. This cross-section isthe same type of cross-section employed by the needle valve of theembodiment of FIG. 7 as well.

FIG. 12A depicts a schematic cross-sectional view of a partialproportioning valve housing having an enhanced set screw configurationfor adjusting spring tension in the embodiments that employ a spring. Asdepicted, partial housing 400 is shown with spring 402 between a springisolator disc 404 at one end and a spring stop 406 at the other end. Theposition of spring stop 406 is set using a removable key or driver 408.In this manner, spring tension may be predetermined in a factory setfixture, or in the field by a specialist having the appropriate driver.In-field adjustment mitigates spring/system variation and facilitatesfunctionality and consistency. The drive key/spring stop interface maybe any shape that allows for adjustment only when the specified drivekey is engaged in the spring stop.

FIG. 12B depicts a schematic isometric view of spring stop 406, showingan opening 410 for receiving driver 408. Opening 410 and complementarydriver key 408 may be any predetermined geometric shape or other keyingmechanism that allows for mating and simultaneously facilitatesrotation.

The proportioning valve of the present invention is designed to be addedto a residential reverse osmosis drinking water system, and specificallya residential reverse osmosis drinking water system that utilizesvarying accumulated pressure in a storage tank as the energy to modulatethe waste water flow in proportion to the product water flow.

While the present invention has been particularly described, inconjunction with a specific preferred embodiment, it is evident thatmany alternatives, modifications and variations will be apparent tothose skilled in the art in light of the foregoing description. It istherefore contemplated that the appended claims will embrace any suchalternatives, modifications and variations as falling within the truescope and spirit of the present invention.

Thus, having described the invention, what is claimed is:
 1. Aproportioning valve for a reverse osmosis system comprising: acylindrical housing having an internal cavity with a product water inletproximate one end of said housing; a reject water inlet downstream ofsaid product water inlet but not in fluid communication with saidproduct water inlet; a reject water outlet downstream of said rejectwater inlet, and in fluid communication with said reject water inlet forat least a portion of the operation of said valve; a slider within saidhousing responsive on a first end to pressure provided by said productwater inlet and on a second end responsive to pressure provided by areverse pressure mechanism designed to partially counter said pressureprovided by said product water, said slider having an axial length and achannel axially located on the outer surface of said slider and having adepth varying along the axial length of said slider, such that thechannel is wider and deeper proximate said second end, and extendingaxially along the axial length of said slider, and exposed to saidreject water inlet, directing said reject water along said axial lengthof said slider, said channel slidably exposed to said reject wateroutlet when said slider moves and said channel is placed in fluidcommunication with said reject water outlet; and at least one o-ringseal in circumferential contact with said second end of said slider andin slidable contact with sidewalls of said internal cavity, to keepreject water from entering a portion of said internal cavity that housessaid reverse pressure mechanism throughout operation of saidproportioning valve.
 2. The proportioning valve of claim 1 wherein saidchannel is V-shaped, semi-circular, square, a flat incline, or othershape having varying width and/or depth and/or length extending axiallyalong a portion of said slider.
 3. The proportioning valve of claim 1wherein said reverse pressure mechanism includes a spring in mechanicalcommunication with said slider at one end, and located within saidinternal cavity.
 4. The proportioning valve of claim 1 wherein saidslider includes a slider extension adjacent to or integral with saidslider, said slider extension extending the axial length of said sliderwith no part of the channel formed in the slider extension, said sliderextension in mechanical communication with said reverse pressuremechanism.
 5. The proportioning valve of claim 1, wherein theproportioning valve is configured to be added to a residential reverseosmosis drinking water system that utilizes varying accumulated pressurein a storage tank as the energy to modulate the waste water flow inproportion to the product water flow.
 6. A proportioning valve for areverse osmosis system comprising: a cylindrical housing having aninternal cavity with a product water inlet proximate one end of saidhousing; a reject water inlet downstream of said product water inlet butnot in fluid communication with said product water inlet; a reject wateroutlet downstream of said reject water inlet, and in fluid communicationwith said reject water inlet for at least a portion of the operation ofsaid valve; a slider within said housing responsive on a first end topressure provided by said product water inlet and on a second endresponsive to pressure provided by a reverse pressure mechanism designedto partially counter said pressure provided by said product water, saidslider having an axial length and a groove having a depth varying alongthe axial length of said slider and a width varying circumferentiallyalong said slider, such that the groove is wider and deeper proximatesaid second end, said groove extending axially along the axial length ofsaid slider, and exposed to said reject water inlet, said grooveslidably exposed to said reject water outlet when said slider moves andsaid groove is placed in fluid communication with said reject wateroutlet, such that said groove directs said reject water along said axiallength of said slider; and at least one o-ring seal in circumferentialcontact with said second end of said slider and in slidable contact withsidewalls of said internal cavity, to keep reject water from entering aportion of said internal cavity that houses said reverse pressuremechanism throughout operation of said proportioning valve.